Mass Point Research Articles

The molecular mass and isoelectric point of plant proteomes

BackgroundCell contain diverse array of proteins with different molecular weight and isoelectric point (pI). The molecular weight and pI of protein play important role in determining the molecular biochemical function. Therefore, it was important to understand the detail regarding the molecular weight and pI of the plant proteins.ResultsA proteome-wide analysis of plant proteomes from 145 species revealed a pI range of 1.99 (epsin) to 13.96 (hypothetical protein). The spectrum of molecular mass of the plant proteins varied from 0.54 to 2236.8 kDa. A putative Type-I polyketide synthase (22244 amino acids) in Volvox carteri was found to be the largest protein in the plant kingdom. However, Type-I polyketide synthase was not found in higher plant species. Titin (806.46 kDa) and misin/midasin (730.02 kDa) were the largest proteins identified in higher plant species. The pI and molecular weight of the plant proteins showed a trimodal distribution. An acidic pI (56.44% of proteins) was found to be predominant over a basic pI (43.34% of proteins) and the abundance of acidic pI proteins was higher in unicellular algae species relative to multicellular higher plants. In contrast, the seaweed, Porphyra umbilicalis, possesses a higher proportion of basic pI proteins (70.09%). Plant proteomes were also found to contain selenocysteine (Sec), amino acid that was found only in lower eukaryotic aquatic plant lineage. Amino acid composition analysis showed Leu was high and Trp was low abundant amino acids in the plant proteome. Additionally, the plant proteomes also possess ambiguous amino acids Xaa (unknown), Asx (asparagine or aspartic acid), Glx (glutamine or glutamic acid), and Xle (leucine or isoleucine) as well.ConclusionThe diverse molecular weight and isoelectric point range of plant proteome will be helpful to understand their biochemical and functional aspects. The presence of selenocysteine proteins in lower eukaryotic organism is of interest and their expression in higher plant system can help us to understand their functional role.

Modeling and Simulation of Moored-Floating Structures Using the Tension Element Method

The derivation of a discrete mooring model for floating structures is presented in this paper. The method predicts the steady-state solution for the shape of an elastic cable and the tension forces under consideration of static loads. It is based on a discretization of the cable in mass points connected with straight but elastic bars. The successive approximation is applied to the resulting system of equations which leads to a significant reduction of the matrix size in comparison to the matrix of a Newton–Raphson method. The mooring model is implemented in the open-source computational fluid dynamics (CFD) model REEF3D. The solver has been used to study various problems in the field of wave hydrodynamics and fluid–structure interaction. It includes floating structures through a level set function and captures its motion using Newton and Euler equations in six degrees-of-freedom (6DOF). The fluid–structure interaction is solved explicitly using an immersed boundary method based on the ghost cell method. The applications show the accuracy of the solver and the effects of mooring on the motion of floating structures.

Pillar array columns for peptide separations in nanoscale reversed-phase chromatography

Reversed-phase chromatography is the most common technique for separation of tryptic peptides. In this short communication, we describe the optimization of sample loading and separation parameters for a novel micromachined column and provide a detailed description on the performance and reproducibility of this separation system. Tryptic digest of a mixture of seven proteins with diverse mass and isoelectric point was used as a test sample. The methods developed and used are straight-forward; by using well-balanced, combined-step gradients an optimal distribution of peptides on the column could be achieved throughout the complete gradient window. The potential use of the column is exceptional due to the low back-pressure, better distribution of peptides over the separation window, enhanced stability and reproducibility of retention times, and the prolonged lifetime of columns compared to conventionally packed nano-HPLC column. The higher identification rates have been demonstrated through measurements of HeLa cell lysates under identical chromatographic conditions on the pillar array and packed-bed columns.

Reevaluation of the body mass estimate for the KNM-ER 5428 Homo erectus talus.

In this study, we reexamined the body mass estimate for the Homo erectus specimen KNM-ER 5428 based on talus dimensions. Previous estimates of >90 kg for this fossil are large in comparison to body mass estimates for other H. erectus specimens. The study sample consisted of tali and femora of 132 modern cadaver males from a documented body mass skeletal collection. We recorded the talus trochlear mediolateral (TTML) breadth and femoral head diameter (FHD) for each modern human specimen, and obtained KNM-ER 5428's TTML values from the literature. We developed regression formulae based on TTML using the body mass estimated from FHD for the entire human sample and for known body masses from a normal-BMI subsample, and then used these formulae to calculate body mass for KNM-ER 5428. In addition, we examined the range of body masses for individuals with TTML measurements comparable to KNM-ER 5428. The body masses of normal-BMI individuals with a TTML ≥32.3 mm (the smaller of the two fossil measurements from the literature) ranged between 60.3 and 86.2 kg and averaged 72.3 kg. The body masses of normal-BMI individuals with a TTML ≥33.7 mm (the larger measurement) ranged between 63.5 and 86.2 kg with a mean of 73.6 kg. The correlations between TTML and body mass are moderate. Revised body mass point estimates for KNM-ER 5428 ranged between 69.2 and 81.6 kg based on TTML, and average 70.5 and 76.0 kg. Results suggest previously published body mass estimates of KNM-ER 5428's are too large. Its body mass was likely between 70 and 76 kg rather than >90 kg.

Development of a Thermal Environment Analysis Method for a Dwelling Containing a Colonnade Space through Coupled Energy Simulation and Computational Fluid Dynamics

In building design, several approaches have been proposed for coupling computational fluid dynamics (CFD) and energy simulation (ES) to perform analyses of thermal environments. The unsteady analysis of thermal environments within buildings containing offices and colonnade spaces is difficult to perform using an ES that represents the space with a single mass point, owing to excessive predictive heat loss; therefore, CFD has typically been used instead. Although it is possible to divide the space into zones using ES, it leads to excessive predicted heat loss and the prediction of heat movement due to the influence of strong air currents, such as those associated with air conditioners. This behavior is observed because these zones are not detailed mesh divisions. To solve these problems, we proposed a method for calculating the ratio of heat contribution to zones that were pre-divided using CFD followed by the distribution of the total thermal load calculated by ES. In this study, we proposed a method for coupling ES and CFD, which enabled the unsteady analysis of a thermal environment in a large space and verified its accuracy.

Dimensions of the Subaxial Lateral Mass: A Systematic Review of Anatomic (Morphometric) Measurement Studies.

This was a systematic review. To review and synthesize information on subaxial lateral mass dimensions in order to determine the ideal starting point, trajectory, and size of a lateral mass screw. The use of lateral mass instrumentation for posterior cervical decompression and fusion has become routine as these constructs have increased rigidity and fusion rates. A systematic search of Medline and EMBASE was conducted. Studies that provided subaxial cervical lateral mass measurements, distance to the facet, vertebral artery and neuroforamen and facet angle made either directly (eg, cadaver specimen) or from patient imaging were considered for inclusion. Pooled estimates of mean dimensions were reported with corresponding 95% confidence intervals. Stratified analysis based on level, sex, imaging plane, source (cadaver or imaging), and measurement method was done. Of the 194 citations identified, 12 cadaver and 10 imaging studies were included. Pooled estimates for C3-C6 were generally consistent for lateral mass height (12.1 mm), width (12.0 mm), depth (10.8 mm), distance to the transverse foramen (11.8 mm), and distance to the nerve. C7 dimensions were most variable. Small sex-based differences in dimensions were noted for height (1.2 mm), width (1.3 mm), depth (0.43 mm), transverse foramen distance (0.9 mm), and nerve distance (0.3-0.8 mm). No firm conclusions regarding differences between measurements made on cadavers and those based on patient computed tomographic images are possible; findings were not consistent across dimensions. The overall strength of evidence is considered very low for all findings. Although estimates of height, width, and depth were generally consistent for C3-C6, C7 dimensions were variable. Small sex differences in dimensions may suggest that surgeons should use a slightly smaller screw in female patients. Firm conclusions regarding facet angulation, source of measurement, and method of measurement were not possible.

Combining release and runout in statistical landslide susceptibility modeling

We introduce and compare two approaches to consistently combine release and runout in GIS-based landslide susceptibility modeling. The computational experiments are conducted on data from the Schnepfau investigation area in western Austria, which include a high-quality landslide inventory and a landslide release susceptibility map. The two proposed methods use a constrained random walk approach for downslope routing of mass points and employ the probability density function (PDF) and the cumulative density function (CDF) of the angles of reach and the travel distances of the observed landslides. The bottom-up approach (A) produces a quantitative spatial probability at the cost of losing the signal of the release susceptibility, whereas the top-down approach (B) retains the signal and performs better, but results in a semi-quantitative score. Approach B also reproduces the observed impact area much better than a pure analysis of landslide release susceptibility. The levels of performance and conservativeness of the model results also strongly depend on the choice of the PDF and CDF (angle of reach, maximum travel distance, or a combination of both).

Massive Point Cloud Space Management Method Based on Octree-Like Encoding

Based on the mass point cloud data, this paper proposes a hybrid octree mixing point cloud index structure which combines the KD-tree spatial segmentation idea to realize the efficient management of mass point cloud. In this paper, the space of the point cloud is firstly divided by the KD-tree idea. On this basis, the octree is used for further segmentation to establish an octree-like index structure. Then the point cloud dataset is spatially encoded using the improved encoding to achieve better spatial management and neighborhood search. Finally, using five groups of incremented point cloud set as test data, the experimental results and comparison analysis show that the octree-like space can make the overall structure of the data organization more reasonable, effectively improve the access efficiency and reduce the occupancy of memory space. The index structure not only improves the speed of the traditional KD-tree construction index but also improves the problem that the traditional octree is too large for space occupation and the neighborhood search takes too long. It achieves reasonable management of massive point cloud space.

A new microbial gluten-degrading prolyl endopeptidase: Potential application in celiac disease to reduce gluten immunogenic peptides.

Gluten is a complex of proteins present in barley, wheat, rye and several varieties of oats that triggers celiac disease in genetically predisposed subjects. Gluten is notoriously difficult to digest by mammalian proteolytic enzymes and therefore, proline-rich digestion-resistant peptides contain multiple immunogenic epitopes. Prolyl endopeptidases (PEP) hydrolyse internal proline residues on the carboxyl side of peptides and have been proposed for food gluten detoxification and as oral enzyme supplementation for celiacs. The aim of this study was to identify new gluten-degrading microbial enzymes with the potential to reduce gluten immunogenicity by neutralizing its antigenic epitopes. Using a gluten-degrading colony screening approach, a bacterial isolate (2RA3) displaying the highest glutenase activity was selected, characterized and its genome completely sequenced. The identification through 16S rDNA gene sequencing showed a 99,1% similarity to Chryseobacterium taeanense. Hydrolysis of gluten immunogenic peptides (GIP) was further monitored, over a 48-hour period, by colony encapsulation in gliadin-containing microspheres, followed by detection with the G12 anti-GIP monoclonal antibody. Glutenase activity was detected in the extracellular medium of 2RA3 cultures, where gel electrophoresis and gliadin zymography revealed the presence of a ~50 kDa gluten-degrading enzyme. Nano-ESI-Q-TOF of the excised active band identified 7 peptides contained in the protein product predicted for an open reading frame (ORF) in the 2RA3 genome. Based on sequence similarity to the PEP family, the new enzyme was named PEP 2RA3. The PEP 2RA3 coding sequence was PCR-amplified from C. taeanense 2RA3, cloned and expressed in Escherichia coli as a C-terminally His-tagged recombinant protein and purified by Ni-NTA affinity chromatography. The recombinant protein, with predicted molecular mass and isoelectric point of 78.95 kDa and 6.8, respectively, shows PEP activity with standard chromogenic substrates, works optimally at pH 8.0 and 30°C and remains stable at pH 6.0 and 50°C, indicating a potential use in gluten-containing food process applications. The ability of the recombinant enzyme to degrade GIP in beer into smaller peptides was confirmed.

Dropwise condensation in the presence of non-condensable gas: Interaction effects of the droplet array using the distributed point sink method

With the presence of NCG, the vapor diffusion from ambient to the vapor/liquid interface must be considered during dropwise condensation. Historically, modeling dropwise condensation often makes the assumption that the droplet is growing in an isolated way. However, the blocking effect of surrounding droplets will tremendously influence the spatial distribution of vapor, which finally determines a different condensation rate comparing with that by the isolated-droplet growth model. Consequently, an accurate prediction for dropwise condensation must include the blocking effect of neighbors (namely the interaction effect). Some classical methods, including the point sink method (PSM) treating the droplet as single point sink, the method of images (MOI) constructing an infinite series of the point sinks in order to satisfy certain boundary conditions, provide a significant improvement comparing the isolated droplet growth model without considering the interaction between droplets. For capturing the strong interaction during dropwise condensation because of a large number of the droplets and the closer inter-droplet spacing, a distributed point sinks method (DPSM) is proposed. Just like in the method of Green’s function with a total mass “sink” responsible for the vapor concentration profile, the condensation droplets are resolved into many mass point “sinks”. For guaranteeing the boundary conditions, for each droplet a series of point sinks are spherically distributed inside the droplet using an average manner. The strengths of the point sinks are solved through a matrix formulation which requires certain boundary conditions and the target points of the droplet surface mapped from the point sinks. Considering some simple droplet arrays and a general droplet array in dropwise condensation, the solutions of DPSM are then compared with those using PSM and MOI. Based on the uniqueness theorem, the exactly satisfied boundary conditions state the ability of DPSM in solving the strong interaction. Finally, the DPSM is used to predict the droplet interactions of a characteristic droplet array from dropwise condensation experiments.

Interval oscillation criteria for second-order linear differential equations with impulsive effects

This paper discusses how the oscillation of solutions changes by adding an impulsive term to a second-order linear differential equation having only a restoring force term but no damping term. Due to the effect of this impulsive term, the moving speed of a mass point of the equation of motion described by the second-order linear differential equation changes discontinuously. Oscillation theorems are given for this impulsive differential equation. As is well known, when the restoring force term is small, all nontrivial solutions of the equation with no impulsive effects do not oscillate. Even when the restoring force term is small, if the action of the impulsive term compensates, the oscillation criteria obtained are satisfied and all nontrivial solutions oscillate. Several examples are given to confirm this fact and some figures are shown to depict the solution curves of these examples. As shown by the obtained oscillation theorems, there are cases that the impulsive effect promotes the oscillation of solutions, but on the contrary, it may suppress the oscillation of solutions. It is shown by a simulation that there is a case where the impulsive effect suppress the oscillation of solutions. Finally, the obtained results are compared with the previous ones.

Parametric evaluation of a heat pipe-radiator assembly for nuclear space power systems

The research and technological development towards compact energy conversion systems for space applications allow the emergence of new mission possibilities, especially those directed for deep space explorations. Besides the final efficiency, the most crucial factor of an energy conversion system for nuclear propulsion purposes is the total mass and size of the system. Considering the Closed Brayton Cycle (CBC) as the energy conversion system for a nuclear power system, a numerical analysis was carried out in order to predict the thermal performance of cold side of the system (i.e., heat pipes and radiator) for initial design purposes. The complete space heat pipe-radiator array was discretized in control volumes where a variation of geometrical parameters was included, resulting in a stepped trapezoidal-shaped radiator (RAD) as output. The heat capacity was limited by the geometry of each panel section, being its heat pipe modeled to fit the given geometry and verified against operational limits. The proposed design-based model considered a physical and thermal coupling with temperature drops along the heat pipe (HP) axial direction, the radiator panel surface, and the cold heat exchanger duct, providing reasonable global parameters to aid the design considering mass and size optimization of a heat pipe-radiator assembly. The number of heat pipes and the total heat pipe-radiator assembly mass and length were evaluated for different heat pipe spacing, heat transfer rate, cold heat exchanger (CHE) inlet temperatures, and radiation shield shadow angles. It was observed a point of minimum HP-RAD mass and length when the heat pipe spacing and CHE inlet temperature are varied, for a given heat transfer rate and shadow angle.

Development of Impact Force 1D Model for Powertrain Component

<div class="section abstract"><div class="htmlview paragraph">Electromagnetic valves excellent in sealing properties and resistant to sliding are often used in powertrain equipment installed in gasoline- or diesel-engine vehicles. An electromagnetic valve has the function of moving internal valve members by means of electromagnetic force generated by the application of a voltage and thereby changing the flow path. When an electromagnetic valve operates, however, the valve members impact with one another, emitting impact noise caused by it. With the requirement for low noise in electromagnetic valves having become stricter recently from the viewpoint of comfort in the passenger compartment, predicting the noise is needed at the design stage.</div><div class="htmlview paragraph">With this background, this paper describes the development of a 1D model of impact force that will enable the noise and the product performance to be examined simultaneously for a GDI (gasoline direct injection) high pressure pump. In contrast to the conventional model in which a movable member is taken as a mass point with a spring and a damper placed at the impact section, this paper proposes a technique in which a spring-mass model with plural mass points is defined a basis on an eigenvalue of the movable member, verifying both models using measurement. In comparison with the conventional model, the proposed model can more exactly calculate the eigenvalues each of the three impact states in the opening operation of an electromagnetic valve. This allows one to improve that the accuracy in calculating the time characteristics of the force.</div><div class="htmlview paragraph">This paper, in addition, gives cases of use of the developed model in studying the reduction of the force. Reducing the stiffness of the member exposed to impact force enabled the reduction in the high-frequency components of the force to be calculated with high precision, and the accompanying reduction in impact noise was confirmed on the actual machine.</div></div>

Optimal Signaling Schemes and Capacity of Non-Coherent Rician Fading Channels With Low-Resolution Output Quantization

Low-resolution analog-to-digital converter (ADC) has been considered as a promising solution to save power and cost in communication systems using high bandwidth and/or multiple RF chains. The goal of this work is to address the design of optimal signaling schemes and establish the capacity limit of Rician fading channels with low-resolution output quantization. This fading channel can be used to accurately model a wide range of wireless channels with the line-of-sight (LOS) components, including emerging mm-wave communications. The focus is on non-coherent fast fading channels where neither the transmitter nor the receiver knows the channel state information (CSI). By examining the continuity of the input-output mutual information, the existence of the optimal input signal is first validated. Then, considering the case of 1-bit ADC, we show that the optimal input is $\pi /2$ circularly symmetric. A necessary and sufficient condition for an input signal to be optimal, which is referred to as the Kuhn-Tucker condition (KTC), and Lagrangian optimization problem are then established. By exploiting the novel log-quadratic bounds on the Gaussian $Q$ -function, it is then demonstrated that for a given mass point’s amplitude, the corresponding rotated mass points through the phase of LOS component must form a square grid centered at zero. Furthermore, the amplitude of the mass points in the optimal distribution can take on only one value. As a result, the capacity-achieving input with 1-bit ADC is a rotated quadrature phase-shift keying (QPSK) constellation, and the rotation angle depends on the Rician factor. The characterization of the optimal input has also been extended to the case of multi-bit ADCs. Specifically, it is shown that for a $K$ -bit ADC, the optimal input is discrete having atmost $2^{2K}$ mass points. In both the cases of 1-bit and $K$ -bit ADCs, the channel capacities are established in closed-form.

Gaussian Mixture Noise Channels With Minimum and Peak Amplitude Constraints

Motivated by the idea of “transmitting energy and information simultaneously,” we investigate, in this paper, the impact of constraints on the amount of energy that individual symbols carry, i.e., minimum amplitude constraints. We consider a Gaussian mixture noise channel with both minimum and peak amplitude constraints. First, we prove that the capacity-achieving input has a discrete distribution with a finite number of probability mass points. Then, we further investigate the number and positions of the probability mass points for the capacity-achieving input. Specifically, when the interference is constant and known at both the transmitter and the receiver, it can be totally eliminated so that the channel operates like an AWGN channel. In this case, we give a theorem to determine whether the optimal input is binary. For more general cases, such as non-binary inputs and non-constant interference, we investigate optimal inputs and capacities via numerical computations.

Influence of the size of a controllable device on time-optimal rotation generated by a moving internal mass

A two-dimensional time-optimal control problem with a state constraint is studied for a closed mechanical system consisting of a mass point and a solid body that interact via internal forces. It is assumed that the mass point is not allowed to move further away from the body's center of mass than a prescribed distance. A control function is found allowing the body to be turned through a given angle in a minimum time by choosing the velocity of the mass point. In the case of reaching the state constraint, the solution is constructed in explicit form via quadratures representing elliptic integrals. A numerical example of using the derived formulas is given.

Proposal for the Location of a Municipal Solid Waste Management Facility for a Metropolitan Region

Only 16 of the 246 municipalities of Goiás State, Brazil, dispose their municipal solid waste (MSW) in licensed landfills. Therefore, this study proposes the host municipality (HM) of the future shared MSW management facility (MSWMF), serving the Metropolitana de Goiânia (MGyn) microregion. First, the potential areas to construct MSW final disposal facilities (landfills) were identified. Subsequently, using mass point geometry, the HM of the proposed MSWMF for MGyn was defined. The results show that only 19.4% of the area of the studied municipalities is available or subject to approval for landfill construction. The HM will be Aparecida de Goiânia, which will process most of the MSW and send the rejects of treated MSW to the landfill that will be established in the neighboring municipality of Hidrolândia. Additionally, this MSWMF will serve 19 municipalities and will have nine waste transfer stations that will receive waste from 17 municipalities, to minimize MSW transport costs.

Stellar evolution of compact stars in curvature–matter-coupling gravity

This paper is devoted to the study of stellar evolution of compact objects whose energy density and pressure of the fluid are interlinked by means of MIT bag model and a realistic polytropic equation of state in the scenario of $f(R,T,Q)$ gravity, where $Q=R_{ab}T^{ab}$. We derive the field equations as well as the hydrostatic equilibrium equation and analyze their solutions numerically for $R+\delta Q$ functional form with $\delta$ being a coupling parameter. We discuss the dependence of various physical properties such as pressure, energy density, total mass and surface redshift on the chosen values of the model parameter. The physical acceptability of the proposed model is examined by checking the validity of energy conditions, causality condition, and adiabatic index. We also study the effects arising due to matter-curvature coupling on the compact stellar system. It is found that maximum mass point lies within the observational range which indicates that our model is appropriate to describe dense stellar objects.

Establishing the Link Between Lean Mass and Grip Strength Cut Points With Mobility Disability and Other Health Outcomes: Proceedings of the Sarcopenia Definition and Outcomes Consortium Conference.

Lack of consensus on how to diagnose sarcopenia has limited the ability to diagnose this condition and hindered drug development. The Sarcopenia Definitions and Outcomes Consortium (SDOC) was formed to develop evidence-based diagnostic cut points for lean mass and/or muscle strength that identify people at increased risk of mobility disability. We describe here the proceedings of a meeting of SDOC and other experts to discuss strategic considerations in the development of evidence-based sarcopenia definition. Presentations and panel discussions reviewed the usefulness of sarcopenia as a biomarker, the analytical approach used by SDOC to establish cut points, and preliminary findings, and provided strategic direction to develop an evidence-based definition of sarcopenia. The SDOC assembled data from eight epidemiological cohorts consisting of 18,831 participants, clinical populations from 10 randomized trials and observational studies, and 2 nationally representative cohorts. In preliminary assessments, grip strength or grip strength divided by body mass index was identified as discriminators of risk for mobility disability (walking speed <0.8 m/s), whereas dual-energy X-ray absorptiometry-derived lean mass measures were not good discriminators of mobility disability. Candidate definitions based on grip strength variables were associated with increased risk of mortality, falls, mobility disability, and instrumental activities of daily living disability. The prevalence of low grip strength increased with age. The attendees recommended the establishment of an International Expert Panel to review a series of position statements on sarcopenia definition that are informed by the findings of the SDOC analyses and synthesis of literature. International consensus on an evidence-based definition of sarcopenia is needed. Grip strength-absolute or adjusted for body mass index-is an important discriminator of mobility disability and other endpoints. Additional research is needed to develop a predictive risk model that takes into account sarcopenia components as well as age, sex, race, and comorbidities.

Mass sensitivity of the three-flavor chiral phase transition

The mass sensitivity of the chiral phase transition of QCD with and without axial $U_A(1)$-symmetry breaking at vanishing and finite quark chemical potential is investigated. To focus on the low-energy sector of QCD, a quark-meson model with three dynamical quark flavors is employed. Non-perturbative quantum fluctuations are taken into account with the functional renormalization group. The inherent ambiguities in fixing the low-energy model parameters away from the physical mass point and their consequences for spontaneous chiral symmetry breaking are discussed in detail and a heuristic parameter fixing scheme motivated by chiral perturbation theory is proposed. The influence of vacuum and thermal fluctuations of quarks and mesons on the order of the chiral phase transition is additionally assessed with a mean-field analysis.